1. Technical Field
The present invention relates to a device for vehicles that includes an electrical cable bunch, a so-called ignition lock, and an antenna located adjacent to the ignition lock that interacts with a transmit/receive device arranged to communicate with a key dedicated to the ignition lock.
2. Background
Essentially all motor vehicles contain a prefabricated cable bunch that contains, more or less, all of the electrical conductors or cables that are necessary in order to tie together all the electrical components of the vehicle into an electrical system. The conductors or cables are thus, when producing the cable bunch, length-wise adapted to the extension they are to have in the vehicle. The conductors/cables are then bunched together with, for example, plastic cable, shrinking tube, or some other kind of plastic casing so that they together form one unit that is referred to as a cable bunch or a cable mat. Associated with each of the various components located in various places around the vehicle that are to be connected to the bunch is a coupling device used to connect the conductors of the cable bunch to the components either via contacts on the components or on cable ends located in the components. In the aggregate, this arrangement composes and is referred to as cabling.
Component(s) that have appeared in modern vehicles are antitheft-systems that comprise (include, but are not limited to) a transmit/receive unit that interacts with one of the ignition keys of the vehicle. For this purpose, the ignition lock of the vehicle is delivered with an antenna assembly associated therewith, and can be equipped with or without an amplifier assembled on the lock at an end where one of the ignition keys of the vehicle is to be entered during use of the vehicle. As in most combustion vehicles, diesel powered vehicles also typically have ignition locks and ignition keys even if they do not control an ignition circuit as such. The antenna located on the lock is connected after the lock and the mat have been assembled together in the vehicle via a contact pair, of which the contact which belongs to the lock can be arranged on a housing which belongs to the antenna and protects it, or on a cable end connected to the antenna or to an amplifier connected to the antenna. A problem in this context is that the currents in the concerned conductors, especially in cases where no amplifier is used, are very small. Additionally, the requirements which are present in vehicle environments give the contacts dimensions which are suitable for vehicles; that is, relatively large dimensions. The combination of large contacts and small currents is unfortunate because poor contact and loose play in the connection can easily arise. As a consequence, so-called fretting can occur.